Garden Phlox - Knowledgebase Question

Every year my garden Phlox get moldy and die from the roots up, and I end up with just the tops that are green. I have had them for about 9 years, I've transplanted them to a different area of the garden and I have also sprayed them to no avail. Would like any help you can give me.

Phlox are usually easy to grow, especially in rock gardens or where the soil is very fast draining. If the soil remains too moist for too long, phlox can develop root rot and/or powdery mildew. Try working organic matter and builder's sand into the bed prior to planting your phlox. Make sure the plants are getting full sunshine (a few hours of light shade are okay in mid-afternoon), and that you water deeply but infrequently. Avoid wetting the foliage (when you water, flood the soil, not the tops of the plants). You might also try growing Phlox maculata, the thick-leaf phlox, with shiny and mildew-resistant foliage. Best wishes with your garden!